Bits and Bitting Part 2: Curb Bits

In our previous post, Bits and Bitting Part 1, we discussed some of the various bit mouthpieces, the types of snaffle bits and how to measure for your snaffle bit. We also discussed how to determine if your horse has a thick or narrow tongue.

But, do you know how to determine your horse’s palate? To determine the room inside the mouth put your index finger in the side of the horse’s mouth where the bit mouthpiece would go. When the horse stops trying to chew your finger, bend your finger and see if it hits the roof of his mouth. If you touch the roof of the mouth, the horse has a low palate. With this knowledge, you now know what type of port you should be looking at.

Parts of a curb bit

The curb bit is different, as it has both curb and poll action and has the reins attached below the mouthpiece so the principle of the lever and fulcrum is in effect. This means that if the cheek or purchase piece of the bit is one inch and the shank is three inches, then the bit is 1 to 3 in leverage. What this means is, if the rider applies one pound of pressure to the reins, three pounds of pressure is applied to the horse’s mouth. Depending upon the type of mouthpiece, pressure can also be applied to the tongue, the bars, the lips and also the roof of the mouth. Typically, as the horse progresses through his education, he is generally asked to work with a curb bit as the lever of the action of the curb bit magnifies the subtle movement of the reins as the rider asks for head and body frame. Use the curb on a horse that knows what to do…knows the positions and has learned the correct responses and understands that by responding quickly and correctly he will be left in a comfortable position.

Low Port Curb

”Grazing” Shank on Low Port Curb

High Port Curb

The Santa Barbara

The Santa Barbara, grazing, sweet water or mullen bits, simply describe the styles of shank or mouthpiece and are still curb bits. Often a jointed mouthpiece curb is mislabeled as a snaffle, but again, it is a curb bit as the mouthpiece does not establish the type of bit.

Jointed Mouthpiece Curb – often incorrectly labeled as a snaffle

Don Blazer, author of many popular equestrian books, describes a couple of complicated but useful ways to determine the mildness or severity of both the snaffle and curb bits.

Following is a rating formula for the snaffle bit: Answer the following questions and give yourself the stated points for each answer as shown.

How many pieces are in the horses mouth?

One to 3 – equals 1 point

More than 3 pieces – 5 points

What is the texture of the mouthpiece?

Sharp (triangular or edged) – 10 points

Twisted wire or chain – 10 points

Twisted metal – 5 points

Wrapped in smooth wire – 2 points

Smooth – 1 point

What is the shape of the cheek piece?

Round (ring or circle) – 1 point

Other shapes (eggbutt, D, full cheek) – 2 points

How thick is the mouthpiece?

½ inch or more – 1 point

3/8 inch – 3 points

Less than 3/8 inch - 10 points

Is it a gag or elevator bit?

Yes = 8 points

No = 0 points

How is the cheek piece attached to the mouthpiece?

Through holes in the mouthpiece – 1 point

All other attachment – 3 points

Are there keys or crickets on the mouthpiece?

Yes = 3 points

No = 0 points

Here’s the complicated part: Add points for question one and two together, then multiply points for question three times the points for question four and add that total to the previous total. Add the points for question five and then subtract the points for questions six, seven and eight.

For example, the most common snaffle bit you see is the loose ring snaffle with a stainless steel 3/8 inch mouthpiece. So, let’s rate this bit:

Using the above formula: Question 1 equals 1, plus question 2 equals 1 for a total of 2. Question 3 equals 1 point multiplied by question 4 with 3 points results in 3 points added to the previous total of 2 equals 5 points. Now add 0 points for a no answer to question 5 and subtract 1 point for question 6, leaving a total of 4 points. Subtract 0 points for question 7 and 0 points for question 8 with the final answer being 4 points.

Using the above formula, bits are mild with a 5 or less points, a moderate bit with 6 to 19 points and severe bit with 20 or more points.

The curb bit rating formula: Again answer the questions assigning the points as shown.

High wide port and the port meets the cross piece in a rounded position = 5 points

Medium or low wide port = 1 point

Unbroken arched mouthpiece = 2 points

Straight unbroken mouthpiece = 3 points

How is the port angled with respect to the bit’s shanks?

Port slopes back more than the shanks = 1 point

Port is parallel to the shank = 1 point

Port slopes forward more than the shank = 10 points

How does the mouthpiece slope side to side?

Jointed mouthpiece with a spacer bar to keep the shanks apart = 1 point

Jointed mouthpiece with no spacer bar, shanks can move toward the center under the jaw = 10 points

Solid mouthpiece which is perpendicular to shanks = 1 point

Solid mouthpiece, which slopes down to the shank = 10 points

How are the shanks bent?

Are they straight = 3 points

Swept back toward horse’s check = 1 point

Are angled forward of mouthpiece = 5 points

How long are the shanks?

1 inch or less = 1 point

More than 1 inch up to 3 inches = 2 points

Over 3 and up to 4 inches = 4 points

More than 4 inches = 7 points

What is the texture or shape of the mouthpiece?

Sharp = 10 points

Twisted wire or chain = 10 points

Twisted metal = 5 points

Wrapped with smooth wire = 3 points

Smooth = 1 point

How thick is the mouthpiece?

½ inch or more = 2 points

Less than ½ inch = 3 points

Where does the curb strap attach?

Same ring as the bridle cheeks = 0 points

Separate ring below ring for bridle = 2 points

Separate ring behind the ring for bridle = 5 points

How are the shanks attached:

Through holes in the mouthpiece as most Pelhams = 1 point

All other including welded solid = 3 points

Are there keys, crickets or a roller on the mouthpiece?

Yes = 3 points

No = 0 points

Is the mouthpiece copper or sweet iron, or does it have copper or iron added to it in any way?

Yes = 3 points

No = 0 points

To rate a curb bit, use the above formula: Add the points together for questions 1, 2, 3, 4 and 5. Now add the points for 6 and 7 together and multiply by the points for question 8. Add that to the previous total and then subtract the points for questions 9, 10, 11 and 12.

Let’s rate a solid jawed which has a low port and a 5 inch shank and is made of stainless steel which, by the way, is the most common and cheapest curb bit. The curb strap attaches in the same ring as the bridle. Here is the rating: Question 1 equals 1 point, question 2 equals 1 point, question 3 equals 1 point, question 4 is 1 point, question 5 equals 3 points for a total of 7 points. Now add the points for questions six (7) and question 7 (1) for 8 points and multiply the points for question 8 which is 2 points for a total of 16 points. Add the 16 points and the 7 points for a total of 23 points, then subtract 0 points for question 9 and subtract 3 points for question 10, for a total of 20, then subtract 0 points for question 11 and 0 points for question 12. Wow….the total is 20 points.

A score of 6 to 19 points would be a moderate bit, a score of less than 6 would be a mild bit and over 20 points is considered severe. So, the bit we just rated above is considered a severe bit! Interesting…

The material used to manufacture bits is also very important. Most horses accept stainless steel very well while most do not like aluminum. Neither material stimulates a lot of moisture in the mouth.

Copper stimulates moisture and horses generally like a full copper mouthpiece, or a mouthpiece with inlaid copper.

Horses really like iron bits and are very delighted by iron with a little rust, (which is disgusting to us as we always want to scrub off that rust, at least I do) which is also known as sweet iron. Iron causes a horse to salivate keeping the mouth moist and soft.

Plastic or rubber bits generally cause a horse to have a dry mouth.

It’s always a good idea to have several bits on hand to choose from as some horses often like a change of bits as they progress through their lessons. However, keep in mind that every horse is an individual and what may work well on one may not work on another.